Marine steering systems have taken numerous forms over the years since power was first provided on water craft. These steering systems have included rudders, articulated drives, including articulated propellers, water jets and the like.
For example U.S. Pat. Nos. 4,929,203 and 3,253,569 disclose marine propeller drive systems in which a propeller is provided which can be pivoted from one position to another, port and starboard, to effectuate steering. U.S. Pat. Nos. 189,603 and 711,886 disclose older versions of this same concept, with the latter patent showing the propeller located within an articulated tube. U.S. Pat. No. 4,310,319 discloses a similar structure.
U.S. Pat. Nos. 6,846,210; 4,509,925; and 3,899,992 disclose propulsion systems with a fixed nozzle surrounding a drive propeller, and use a rudder or the like in the conventional manner for steering.
U.S. Pat. No. 2,139,594 discloses a steering drive for a marine propulsion system in which a nozzle is pivotally mounted for movement about a fixed drive propeller.
As seen from some of the above noted references, the use of a nozzle around a propeller in order to improve drive efficiency was first described many years ago and the modification of such nozzles to cause them to be moved with the propeller for steering purposes followed at about the same time. Generally, such nozzles have been attached to the vessels on which they are used in much the same way as rudders are, that is, with a steering shaft depending vertically upward and a pintle depending vertically downward to provide an axis of pivot for the nozzles, with bearings supporting both. This required direct attachment of the nozzle to the vessel.